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CT理论与应用研究（中英文） 2005年第2期14卷 1-5页

作者：邵立康刘俊旭迟权德韩裕生解放军炮兵学院安徽合肥230031

本文在分析基于CBS的人身安检图像基础上,提出了基于数学形态学膨胀累加、双阈值分割的违禁品分割算法。采用形态学的膨胀累加算法可以有效抑制噪声并提高目标能量;利用连通性判断获得违禁品候选区域;最后通过获得的数据对违禁品目标进... 详细信息

本文在分析基于CBS的人身安检图像基础上,提出了基于数学形态学膨胀累加、双阈值分割的违禁品分割算法。采用形态学的膨胀累加算法可以有效抑制噪声并提高目标能量;利用连通性判断获得违禁品候选区域;最后通过获得的数据对违禁品目标进行有效地凸现。

关键词：康普顿背散射双阈值分割数学形态学连通域

Time-dependent squeezing deformation mechanism of tunnels in layered soft-rock stratum under high geo-stress

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Journal of Mountain Science 2021年第5期18卷 1371-1390页

作者： CHEN Zi-quan HE Chuan WANG Jun MA Chun-chi Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Sichuan Highway Planning Survey Design and Research Institute Ltd Chengdu 610041China Key Laboratory of Engineering Structures of Heavy Haul Railway Ministry of EducationCentral South UniversityChangsha 410075China

Large squeezing deformation of layered soft rock tunnel under high geo-stress has a significant time-dependent deformation *** this paper,we studied the deformation mechanism during the construction period of deep-buried softrock tunnel by means of a combination of field observations and a numerical ***,a new classification criterion for large deformations based on the power exponent variation law between the deformation and the strength-stress ratio is ***,the initial damage tensor reflecting the bedding plane(joint)distribution and an equivalent damage evolution equation derived from the viscoplastic strain are introduced based on the geometric research method,i.e.,a new rheological damage model(RDL model)of layered soft rock is established consisting of elastic,viscous,viscoelastic,viscoplastic and plastic elements.A field test was conducted on the Maoxian tunnel in Sichuan province,southwestern china,which is in broken phyllite(layered soft rock)under high *** tunnel has experienced large deformation due to serious squeezing pressure,thus we adopted double primary support method to overcome the supporting structure failure *** rheological parameters of phyllite in the Maoxian tunnel were recognized by using SA-PSO optimization,and the RDL model does a good job in describing the time-dependent deformation behavior of a layered soft-rock tunnel under high ***,the RDL model was used to investigate the supporting effect and bearing mechanism of the double primary support *** with the single primary support method,the surrounding rock pressure,secondary lining force,surrounding rock deformation,and the depth of the damage to the rock mass was reduced by 40%-60%after the double primary support method was used.

关键词： Deformation mechanism Layered soft rock tunnel High geostress Large squeezing deformation Rheological damage model

Measured overall effusion cooling effectiveness over a wide blowing ratio range using infrared imaging

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航空动力学报 2010年第7期25卷 1454-1463页

作者： ZHANG chi SONG Bo LIN Yu-zhen XU quan-hong LIU Yan National Key Laboratory of Science and Technology on Aero-Engines School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China Jiangsu chinfan Compressor Incorporation Changshu Economic Development Zone Jiangsu 215513 China china North Vehicle Research Institute China North Industries Group Corporation Beijing 100072 China

Experimental investigations were performed on the overall cooling effectiveness η of a flat effusion wall over a wide range of blowing ratio(M=0.47～5.27).The effusion wall had a staggered multi-hole pattern typical of gas turbine combustor application,with a ratio of hole pitch to row spacing P/S=1∶2,a porosity PS/d2=72,and an inclination angle α=30°.The current paper documented distribution of the overall cooling effectiveness on the wall surface,based on infrared imaging of the 2-D surface temperature *** results indicate:(1) The overall η increases along with the streamwise distance for the wide range of M due to the superposition effect of the multi-row film cooling.(2) The overall η substantially benefits from the multi-hole inside convective *** hole convective cooling not only complements the weakest film protection at initial rows but also helps mitigate the temperature gradient.(3) The overall η increases asymptotically with increasing M,unlike adiabatic η mostly published in the past,which decreased after M reached a specific *** current work showcased the end cooling outcome jointly driven by the filming cooling mechanism and the hole inside convective cooling mechanism.

关键词： gas turbine effusion cooling overall cooling effectiveness blowing ratio infrared imaging

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基于双空间矢量调制方法分析矩阵变换器

电子设计工程 2011年第8期19卷 170-172,178页

作者：陶彦辉沈建华苏建徽迟权德合肥炮兵学院基础部安徽合肥230031 教育部光伏系统工程研究中心合肥工业大学能源研究所安徽合肥230009

矩阵变换器的控制是一项复杂的任务。对矩阵变换器应用双空间矢量调制方法进行了详尽的分析,利用Mat-lab/Simulink软件并借助于其中的S函数进行了仿真。结果证明,这种调制策略使整个调制时间缩短,设计可靠,矩阵变换器复杂的控制过程被... 详细信息

矩阵变换器的控制是一项复杂的任务。对矩阵变换器应用双空间矢量调制方法进行了详尽的分析,利用Mat-lab/Simulink软件并借助于其中的S函数进行了仿真。结果证明,这种调制策略使整个调制时间缩短,设计可靠,矩阵变换器复杂的控制过程被简化了,输出线电压是正弦性很好的PWM波形。给实际研究和设计提供了方便。

关键词：矩阵变换器 Matlab/Simulink 双空间矢量调制 S函数占空比

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四方形钯纳米片的控制合成

中南民族大学学报（自然科学版） 2013年第3期32卷 5-7页

作者：黄涛李灿吴静周忠强池泉刘汉范中南民族大学化学与材料科学学院催化材料科学国家民委-教育部重点实验室武汉430074

以PdCl2为前躯体,三缩四乙二醇(TEG)为溶剂和还原剂,聚乙烯吡咯烷酮(PVP)为保护剂,在一定量KI存在下,于160℃油浴下反应3h,合成了形貌单一、大小均匀的四方形钯纳米片,产物用透射电子显微镜(TEM)、X-射线粉末衍射(XRD)、X-射线光电子能... 详细信息

以PdCl2为前躯体,三缩四乙二醇(TEG)为溶剂和还原剂,聚乙烯吡咯烷酮(PVP)为保护剂,在一定量KI存在下,于160℃油浴下反应3h,合成了形貌单一、大小均匀的四方形钯纳米片,产物用透射电子显微镜(TEM)、X-射线粉末衍射(XRD)、X-射线光电子能谱(XPS)等进行了表征.

关键词：钯四方形纳米片三缩四乙二醇聚乙烯吡咯烷酮

Effect of stress paths on failure mechanism and progressive damage of hard-brittle rock

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Journal of Mountain Science 2021年第9期18卷 2486-2502页

作者： CHEN Zi-quan HE Chuan HU Xiong-yu MA Chun-chi Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Engineering Structures of Heavy Haul Railway Ministry of EducationCentral South UniversityChangsha 410075China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

During deep buried hard-brittle rock tunnel excavation,the surrounding rock experiences a complicated stress path and stress adjustment *** the adjusted stress exceeds the ultimate bearing capacity of rockmass,a rock failure mode defined as stress-cracking type will *** order to investigate the effect of stress paths on failure mechanism and progressive damage of deep-buried rockmass,the cyclic loading-unloading,loading-unloading,uniaxial,conventional and unloading triaxial compression tests on samples of hard-brittle sandstone were *** to the experimental results,increase in the confining pressure was beneficial to improve the mechanical parameters of rock,but it will reduce the brittle failure *** with conventional triaxial compression,the sandstone under unloading state had more remarkable stress drop and unstable failure ***,it was found that the energy dissipation and energy release in the whole process of rock deformation were the internal power of driven rock progressive *** the increase of confining pressure,the energy hardening and energy accumulation features of rock were weakened,while the progressive damage evolution characteristics could be *** unloading state,more energy could be converted into elastic energy in the energy softening phase(σeb-σP),so that the prepeak damage rate of rock was lower than that of conventional triaxial compression ***,the energy dissipation rate of rock after peak strength decreased linearly with the increase of confining pressure under conventional triaxial compression state,while in unloading state it showed the opposite law.

关键词： Hard-brittle rock Stress path Confining pressure Failure mechanism Progressive damage

Isotropic Thermal Cloaks with Thermal Manipulation Function

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chinese Physics Letters 2021年第1期38卷 24-29页

作者： quan-Wen Hou Jia-chi Li Xiao-Peng Zhao Smart Materials Laboratory School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710129China

By extending the conventional scattering canceling theory,we propose a new design method for thermal cloaks based on isotropic *** the objects are covered by the designed cloaks,they will not disturb the temperature profile in the background *** addition,if different inhomogeneity coefficients are selected in the thermal cloak design process,these cloaks can manipulate the temperature gradient of the objects,i.e.,make the temperature gradients higher,lower,or equal to the thermal gradient in the background ***,thermal transparency,heat concentration or heat shield effects can be realized under a unified framework.

关键词： materials. thermal gradient

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花片状钌纳米颗粒的控制合成

化学与生物工程 2013年第2期30卷 24-26,35页

作者：吴静李灿周忠强池泉黄涛刘汉范中南民族大学化学与材料科学学院催化材料科学国家民委-教育部重点实验室湖北武汉430074

以三氯化钌为前驱体、聚乙烯吡咯烷酮(PVP)为稳定剂、三缩四乙二醇(TEG)和Zn粉为还原剂,于170℃反应2h,再加入适量十六烷基三甲基溴化铵(CTAB),继续反应4h成功制得花片状Ru纳米颗粒。反应体系中最适宜RuCl3∶PVP∶CTAB∶Zn(摩尔比)为1... 详细信息

以三氯化钌为前驱体、聚乙烯吡咯烷酮(PVP)为稳定剂、三缩四乙二醇(TEG)和Zn粉为还原剂,于170℃反应2h,再加入适量十六烷基三甲基溴化铵(CTAB),继续反应4h成功制得花片状Ru纳米颗粒。反应体系中最适宜RuCl3∶PVP∶CTAB∶Zn(摩尔比)为1∶20∶1∶1.5。产物用透射电子显微镜(TEM)、X-射线粉末衍射(XRD)、紫外可见吸收光谱(UV-Vis)等进行了表征。

关键词：钌花片状三缩四乙二醇聚乙烯吡咯烷酮十六烷基三甲基溴化铵

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铂纳米花的控制合成

化学与生物工程 2012年第5期29卷 19-21,30页

作者：李甘朱海池泉赵燕熹刘汉范黄涛中南民族大学催化材料科学湖北省暨国家民委-教育部重点实验室湖北武汉430074

以氯铂酸钾(K2PtCl6)为前驱体、聚乙烯吡咯烷酮(PVP)为稳定剂及还原剂,在一定量溴化钾(KBr)的存在下,采用水热法制备了铂纳米花。考察了n(K2PtCl6)∶n(PVP)∶n(KBr)、反应温度、反应时间对产物形貌的影响。结果表明,在n(K2PtCl6)∶n(PVP... 详细信息

以氯铂酸钾(K2PtCl6)为前驱体、聚乙烯吡咯烷酮(PVP)为稳定剂及还原剂,在一定量溴化钾(KBr)的存在下,采用水热法制备了铂纳米花。考察了n(K2PtCl6)∶n(PVP)∶n(KBr)、反应温度、反应时间对产物形貌的影响。结果表明,在n(K2PtCl6)∶n(PVP)∶n(KBr)为1∶10∶15、反应温度为130℃、反应时间为3h的条件下,制备出形貌规则、大小均匀的花形自组装铂纳米颗粒。利用透射电子显微镜、X-射线光电子能谱和X-射线粉末衍射对产物进行了表征。所制备的铂纳米花由零价态的铂原子组成,具有面心立方(fcc)结构。

关键词：铂纳米花氯铂酸钾水热法聚乙烯吡咯烷酮

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基于概念基元的句群情景框架抽取研究

微计算机应用 2010年第4期31卷 21-24页

作者：韦向峰缪建明张全池毓焕中国科学院声学研究所北京100190

句群的构成要素是领域、情景和背景,领域是核心。领域关联的情景框架主要依据领域句类知识库的描述,从句群语句的语义块中抽取。本文介绍了在语言概念空间中对句群情景框架的概念符号描述,通过匹配整合句群情景框架中语义块的概念约束... 详细信息

句群的构成要素是领域、情景和背景,领域是核心。领域关联的情景框架主要依据领域句类知识库的描述,从句群语句的语义块中抽取。本文介绍了在语言概念空间中对句群情景框架的概念符号描述,通过匹配整合句群情景框架中语义块的概念约束和句类分析结果中的语义块,给出了从自然语言空间的句群中抽取情景框架要素的方法,并根据实验结果总结了句群情景框架抽取中需要加强和完善的地方。

关键词：句群情景框架领域句类语义块句类分析